A natural anatomy includes several anatomical portions that are generally able to articulate relative to one another in a substantially pain-free and natural manner. For example, a glenoid can articulate with a humerus or an acetabelum can articulate with a femoral head. For various reasons, however, the various anatomical portions may become damaged or not operate in a natural manner. Due to various reasons, for example, injury or disease, the anatomical portions can become damaged. Once an anatomical portion has become damaged, under certain circumstances, a prosthesis can be positioned relative to the remaining anatomical portions to allow for mimicking the natural anatomical motion. For example, an acetabular implant can be positioned relative to an acetabulum, a femoral head implant can be positioned relative to a femur, or other various prosthesis can be positioned in the anatomy to allow for obtaining or repairing natural anatomical motion.
Various anatomical implants can be positioned relative to the anatomy using various procedures. Generally, an open procedure can be used to position a prosthesis relative to the anatomy. In an open procedure, an incision is formed through the soft tissue, which can include adipose tissue, muscle tissue, skin tissue and the like. The open incision allows for access to the entire anatomical area to be replaced, such as a large incision over a substantial portion of the knee joint, the hip joint, or the like. The damaged anatomical portions can then be generally removed to allow for placement of the prosthesis members. In a hip joint, the acetabulum may be reamed and an acetabular implant may be positioned relative to the reamed actabelum.
Generally, an implant may include a portion that allows it to be fixed to the anatomy and a second portion that allows it to articulate with another portion of anatomy or another implant. It may be that the various portions are formed as a single member or formed as multiple members. Nevertheless, the large incision generally allows for ease of access to the natural anatomical portions and for implanting the prosthesis.
It is desirable, however, to allow for the same ease of implantation with use of a smaller incision. A less or minimally invasive procedure can include forming an incision that is only large enough or not substantially larger than the size of the prosthesis or portions of the prosthesis to be implanted in the anatomy. To perform such a procedure, it is desirable to provide instruments that allow for ease of positioning the various portions of the prosthesis and for preparing the anatomy for implantation of the prosthesis while maintaining maximum efficacy of the procedure.